[PATCH 1 of 2] ui: write prompt text in ui.prompt(), not in ui._readline()

[Yuya Nishihara]

# HG changeset patch
# User Yuya Nishihara <yuya at tcha.org>
# Date 1517830849 -32400
#      Mon Feb 05 20:40:49 2018 +0900
# Node ID 9be8a0f8d48502734066a66e3d5b9b22e460ae70
# Parent  a9802c9ecfb5aa20d89480763ae15b03f78f3a88
ui: write prompt text in ui.prompt(), not in ui._readline()

self.label() is replaced by label= option, which should make it clearer why
we can't pass the text to raw_input(prompt).

diff --git a/mercurial/ui.py b/mercurial/ui.py
--- a/mercurial/ui.py
+++ b/mercurial/ui.py
@@ -1246,7 +1246,7 @@ class ui(object):
 
         return i
 
-    def _readline(self, prompt=''):
+    def _readline(self):
         if self._isatty(self.fin):
             try:
                 # magically add command line editing support, where
@@ -1258,11 +1258,6 @@ class ui(object):
             except Exception:
                 pass
 
-        # call write() so output goes through subclassed implementation
-        # e.g. color extension on Windows
-        self.write(prompt, prompt=True)
-        self.flush()
-
         # prompt ' ' must exist; otherwise readline may delete entire line
         # - http://bugs.python.org/issue12833
         with self.timeblockedsection('stdio'):
@@ -1281,8 +1276,10 @@ class ui(object):
         if not self.interactive():
             self.write(msg, ' ', default or '', "\n")
             return default
+        self.write(msg, label='ui.prompt', prompt=True)
+        self.flush()
         try:
-            r = self._readline(self.label(msg, 'ui.prompt'))
+            r = self._readline()
             if not r:
                 r = default
             if self.configbool('ui', 'promptecho'):